fitch



c. M. FITCH.

ADDING MACHINE.

APPLICATION FILED JUNE 25, I9I7-r Patnted Aug. 10, 1920.

a sums-sues? I.

C. M. FITCH.

ADDING MACHINE. APPLICATION FILED JUNE 25. I9.

Patented Aug. 10, 1920.

3 SHEETS-SHEET 2.

I 11 I/ aw/mm i/// WAY/m a q" 551 Z= UNITED STATES PATENT OFFICE.

CHARLES M. FITCH, OF CHICAGO, ILLINOIS, ASSIGNOR, BY MESNE ASSIGNMENTS,T0 BIRD ADDING MACHINE COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OFILLINOIS.

To all whom it may concern:

Be it known that 1, CHARLES MAXIMILIAN Frrorr, a citizen of the UnitedStates of Jamiary 5, 1915, and in patent to Sweet 6t aZ.,

No. 1,128,546, February 16, 1915.

' The main objects of the invention are to provide adding machines ofthe type mentioned with improved mechanisms requiring fewer parts andbeing simpler I in action than is the case with the devices shown insaid patents; and to provide an improved dill'erential mechanism and animproved carrying mechanism.

An illustrative embodiment of this invention is shown in theaccompanying draw ings, in which Figure 1 is a plan view of the with thecover removed.

Fig. 2 is a fragmentary plan view of the device with the main numeraldisk omitted.

Fig. 3 is a transverse vertical section taken on the line A-'A ofFig. 1. i

Fig. 41 is a side elevation of disk or wheel."

Fig. 5 is a detail in elevation of a spring device the hundreds pressedlocking device for the hundreds wheel. g

Fig. 6 is a sectional detail in elevation, of a support forthe transferpawl and the yoke shown in Figs. 2 and 3.

Fig. 7 is a longitudinal section taken on the line B-B of Fig. 1. r

F ig. 8 is a bottom plan View of a ratchet and transfer cam. N

Fig. 9 is an enlarged detail in section of the transfer pawl, taken onthe line C-C of Fig. 2. 5 i

In its main features, the present device comprises a horizontallyrotatable numbered disk which is connected to a spring motor normallyurging the disk to rotate in a lefthand direction and to progressivelyexhibit numbers on its upper surface, through a sight opening providedin the cover of the machine. The controlling keys are pivotally mountedon an arc with respect to the center nnING- AcHInE.

Specification of LettersPatent. Patented Aug. 10, 1920. Applicationfiiea June 25,'1917. Serial No. 176,742. I I

of said disk and are arranged to release the disk and permit. it torotate under the action of the spring motor until an oscillating membermovable with the disk engages *the inner end'of a depressed key.Adjacent the disk is a higher order wheel arranged to r0- tate around ahorizontal axis and to exhibit Transfer mechanism is provided betweenthe numbered disk and the higher order wheel, which is operative in anadding and subtracting direction, so that it will transfer correctlywhen amounts, areadded to the lower order disk and also when the lowerdisk is reversely rotated to its zero position. In this manner, bothdisks may be restored to zero, by merely backwardly rotating the spindlewhich carries the lower order disk. I This spindle is connected to theinner end of a SPlltlSPI'lUg which constitutes-the motor for operatingthe device. Thus,upon resetting operations, the spring is wound, therebyreceiving the required energy for operating the device under the controlof the numeral keys. i

The operating mechanism of the device is mounted on a sheetmetal frame 1which rests within a flanged base plate 2. The

operating'keys are pivotally mounted on an arcuate rod 3 wlnch in turnis supported in a frame member 41 secured to the frame 1'.

frame 4-. The keys are depressible against the action of the springs12.1, and their rear ends 13 extend beneath an arc-shaped bail 1 1, theparallel arms 15 of which'are bent to pass through apertures 16 in thestandards or upwardly bent portions 17 of the lower bearing plate 18 ofthe spindle 10. The plate 18 is secured to the frame member 1.

' its numerals through the same sight opening.

The upper end of the spindle 10 is journalefd in aplate 19 which is bentto'U-form and is secured to the plate 18 and the'frame 1 by the screws20 (Fig. 1).

The lower order numeral disk 21 is se- .cured to a cylindrical member 22pinned to the spindle 10 and serving as a hub for the numeral disk 21and ratchet wheel 23,

thus compelling the numeral disk and ratchet wheel to rotate as a unitwhen rotary motion is imparted to the spindle 10. F or the .purpose ofreceiving motion from and also winding the spring motor 24 (Fig. 3), thespindle 10 carries at its lower end a pinion 25 meshing with a gear 26fast to the motor spindle 27 to which the inner end of the spring 24 issecured. The outer end of the spring is secured to a post 28.

For the purpose of imparting differen tial motion to the disk 21 underthe control of the keys 9.1, an arm 30 is rotatably mounted on thecollar 22 in an annular groove 31 therein, This groove is of rounded orV-form, forthe purpose of permitting the arm 30 to oscillate verticallywhile preventing it from sliding vertically on its journal. The forwardend 32 of the' arm is loosely curled around the arenate bar or bail 14.Thus, when a key is depressed and the bail is rocked upwardly, the arm30 will also swing upwardly, and the arm is provided with a pointed pin3?) for entering the adjacent hole of a series of annular perforations34 in the numeral disk 21..

After the point of the pin 33 has entered one of the perforations in thenumeral disk,

further upward motion of the bail 14 re-.

sults in disengaging a pawl 35 (Fig. 2) from the ratchet wheel 23. Themeans for disengaging the pawl comprises an arm 36 fast to one end ofone of the arms 15 of the bail 14. The arm 36 engages a shouldenil'? onthe pawl 35 and in this manner rocks the pawl away from the ratchetwheel, around its pivot 38 against the action of the spring 39. Thenumeral disk then rotates in a forward direction under the ction of thespring member 24, and since the pin 33 engages the numeral. disk,-thearm 30 will be rocked with the disk until it engages the portion 13 ofthedepressed key. Thus, the angular motion of the disk 21 is determinedby the angular position of the depressed key with respect to the spindle10. If the 1 key is depressed, the disk will rotate only one unit, orone one-hundredth of a rotation, whereas if the 18 key is depressed, thedisk will rotate eighteen one-hundredths of a rotation.

The higherorder wheel 40 consists of a drum having 10 divisions numberedfrom 1 to 10. This wheel is rotatably mounted on a stub shaft 41extending inwardly from one of the vertical arms of the bracketshapedframe member 19. The wheel 49 is normally prevented from rotating by alug 42 engaging the wheel at one of the ten perforations 48 therein. Thelug 42 projects from the lowerend of a ring 44 located within the wheel40 and encircling the stub shaft 41. This ring is mounted to oscillatevertically around a pair of pins 45 extending from the frame 19. Thespring 46 normally urges the ring 44 to rock in such direction as towheel 40.

The transfer mechanism cons sts of a reciprocating and oscillatingmember 3-? (his. 2) having a pointed end 48 adapted to enter one of theperforations 43 in the higher order wheel, either to the right or theleftof the perforation which is engaged by the lug 42. The end 48 whenentering one of said perforations rocks the ring 44 around the pins 45,disengaging the lug 42 from the wheel 40. The wheel then is under thecontrol of the member 47 and is turned thereby in additive orsubtractive direction, one unit for each complete rotation of thenumeral disk 21, respectively, on adding or resetting operations. Forthe purpose of projecting the member 47 into engagement with the wheel40, a small post 49 projects downwardly from the ratchet wheel 23.

This post is in a suitable location to engage the rear end 50 of a slidemember 51 at the time the wheel 21 passes from 99 to O, or from 0 to 99.The slide member 51 is provided with legs 52 resting on the fixed plate18 between the flanges thereof. The slide 51 is also provided with pins54 projecting. through curved slots in the carryingdevice 47. Thus onthe motion of the slide 51 under the action of the pin 49, the carryingdevice/l7 is projected into engagement with the wheel 40, due to thepins 54 engaging the ends of the slots The transfer device may then,oscillate on either one of the pins 54 as the slot 55, engaged by theopposite pin, permits such motion. The transfer device 47 is normallyretained in a central position, as Sl1()\ n in Fig. 2, by a spring 56.(Fig. 9') extending between the lug 57. on the transfer device 47 and ascrew 58 depending from the slide member 51. The inner end of thetransfer device 47 is curved as shown in Fig. 2, and is bent upwardly at59 for the purpose of cooperating with a semi-spiral actuating cam 10secured to the lower surface of the ratchet wheel 23; The normalposition of the lug 59 being as shown in Fig. 2, the cam 60 will rockthe transfer device 47 either to the right or the left, depending uponthe direction of rotation of the ratchet wheel. Since in addingoperations the ratchet wheel rotates in the direction indicated. by thearrow 61 (Fig. 2) the lug 59 will be engaged by the inside surface ofthe cam, and the transfer device, during the rotation of the cam, willbe gradually rocked to the left, around the pin 54. When thetransferdevice is in its extreme left-hand position, the pin 49 projects thetransfer device into engagement with the wheel 40, and before thepin 49clears the inner end of the slide 51, the cam 60 releases the transferdevicc 4'7, which then oslock the cillates back to its normal positionas shown in Fig. 2. i This rocking motion of the transfer deviceresultsv in the higher order wheel 40 rotating one unit of movement in aforward direction.

On resetting operations, the ratchet 23 is rotated oppositely to thedirection indicated by the arrow 61, and therefore the outer surface ofthe cam 60 engages the lug 59 and rocks the transfer device at?outwardly around the pin 54L, and when it releases the same, permits itto return to its normal position and rotate the wheel 40 backwardly oneunit for each complete backward rotation or" the wheel 21. In resettlngthe device, backward IOtittlOIl.

is imparted to the spindle 10 by means of the crank handle 62, which hasa slotted hub 3 formed to engage a transverse pin (34 in the upper endof the spindle. Since the disk 21 and ratchet wheel 23 are fast tothespindle, the wheel 21 is rotated backwardly, and the transfer deviceoperated for each backward rotation of the numeral wheel 21 to impartone unit of backward motion to the higher order wheel lO. WVhen thelatter wheel arrives at zero position, the disk 21 will also be at zeroposition, and further backward motion is prevented by an arm 65engaging'the spindle '10. The arm 65 is fast to a pinion 66 rotatablymounted on the stub shaft 67, which is driven one tooth space for eachcomplete rotation otthe spindle 10 in either direction, by a pin 68projecting from the spindle in the horizontal plane of the pinion 66.The arm (35 therefore may be rotated in either direction until stoppedby engagement with the spindle 10, and determines the maximum amountwhich may be accumulated by the numeral wheels, and also preventsrotation of such wheels beyond the zero position upon resettingoperations. The retaining pawl for the pinion 66 is indicated at 66.1.

In the operation of the device, assuming that each of the numeral wheelsindicates zero, a depression of the key will result in rocking thearcuate'bar l l upwardly thereby causing the pointed pin 35 to engageone of the perforations 34 in the numeral disk 21. The arm 30, beingcapable of rotation around the spindle 10, may then rotate with thenumeral disk 21 under the action of the spring motor 24 until said armis stopped by engagement with the rearend 13 of the depressed key. '1 hemotor is permitted. toact' action of the motor. As the arcuatev bar 14retu'rnsto normal position, it disengages the pin 53 from the disk 21,due to the fact that the outer end oi the arm 33 is loosely curledaround the bar 14h As amounts are successively added. to the numeralwheel 21, the cam (30 serves to rock the transfer device l! around itspivot .5 in a leit-hand direction. The transfer device is then projectedinto one or the apertures in the hi her order wheel, by the pin 49engag= ing the slide 51 upon which the transfer de vice is mounted.

normal oosition carr' in with it the transl a a fer device l? undertheaction of the spring 51.1. Theslide 51 1s glllClQCllIl itsreciproeating motion by the fixed plates 18 and 18.1. i

lVhen the numeral wheel 21 arrives at zero position, the lug 59 of- Thedevice may be reset to zero at any time, merely by rotating the s ind le10 in a right-hand direction (Fig. 2), by means oi. the crank handle 62.In this direction of rotation the spindle, the teeth of the ratchet 23idly ride over the end of the pawl 35. Each time the disk 21 passes thezero point, the transfer device will be operated in a subtractivedirection, due to the return rocking motion of the transfer device underthe action of its spring 56 when it is released by the cam 60, whichupon resetting operations, normally serves to rock the transfer deviceto the right (Fig. 2). lV hen the higher orderwheel arrives at zeroposition, the arm (35, by engaging the spindle 10, prevents furtherrotation of the pinion 66, and consequently, rotation oi the numeralwheels beyond their zero position.

Althoughbut one specific embodiment of this invention has been hereinshown and described, it will be understood that numerous details of theconstrin ion shown may be altered. or omitted without departing "fromthe spirit of this invention as defined b the followin claims.

I claim:

1. A device of the class described, comprising a numbered rotatabledisk, a spring for rotating said disk, a ratchet wheel rigid with saiddisk, a pawl for engaging said ratchet wheel and normally preventingrotation of the disk under the action of the spring, an arm arranged tooscillate around the axis of said disk and to rock vertically into andout of engagement therewith, and manipulative devices adapted todisengage said pawl from the ratchet and limit the rotation of thenumbered disk by cooperating with said arm.

2. A device of the'class described, cornprising a numbered rotatabledisk, a spring for rotating said disk, a ratchet wheel rigid with saiddisk, a pawl for engaging said ratchet wheel and normally preventingrotation of the disk under the action of the spring, an arm arranged tooscillate around the axis of said disk and to rock vertically into andout of: engagement therewith, a pivoted bail for rocking said armvertically, said bail being arranged to rock the pawl out of engagementwith the ratchet wheel, and keys radially arranged with respect to theaxis of said numbered disk and adapted to rock said bail and limit therotation of the disk by cooperating with said arm.

3. A device of the class described, comprising a numbered rotatabledisk, a spring for rotating said disk, a ratchet wheel rigid with saiddisk, a pawl for engaging said ratchet wheel and normally preventingrotation of the disk under the action of the spring, an arm arranged tooscillate around the axis of said. disk and to rock vertically into andout of engagement therewith, a pivoted bail for rocking said armvertically, said bail being arranged to rock the pawl out of engagementwith the ratchet wheel. and manipulative means adapted to rock said bailand limit the rotation of the disk by cooperating with said arm.

at. A device of the classdescribed, comprising a lower ordernumeralwvheel and a higher order numeral wheel, means for differentiallyrotating the lower order wheel, a transfer device, a slide upon whichsaid transfer device is pivotally mounted, an open spiral cam rigid withthe lower order wheel arranged to rock said transfer device around itspivot in adirection dependent upon the direction of rotation of saidlower order wheel, means for shifting said slide to engage the transferdevice with the higher order wheel, and means for rocking the transferdevice around its pivot back to normal position.

5. A device of the class describech comprising a lower order numeralwheel and a higher order numeral wheel, means for differentiallyrotating the lower order wheel, a transfer device, a slide uponwhichsaid transfer device is pivotally mounted,

an open spiral cam rigid with the lower order wheel arranged to rocksaid transfer device around its pivot in -ad rection dependent upon thedirection of rotation of said lower order wheel, means for shifting saidslide to engage the transfer device with the higher order wheel, and aspring for rocking the transfer device around its pivot back to normalposition.

(S. A device of the class described, comprising a lower order wheel anda higher order wheel, a spring motor arranged to drive said lower orderwheel, manipulative means for controlling the rotation of the lowerorder wheel under the action of said spring motor, carrying mechanismbetween said lower and higher order wheels, said carrying mechanismcomprising an oscillating pawl for engaging the higher order wheel, aslide upon which said pawl is mounted, said slide being shiftable underthe action of said lower order wheel, and a double pivotal connectionbetween said pawl and slide, said lower order wheel being arranged tooscillate said pawl around one or the other of the slot and pinconnections with said slide according to the direction of rotation ofsaid lower order wheel, and a restoring sprii'ig extended between saidslide and pawl.

7. A device of the class described, a. numeral disk, a spring motor fordriving said disk, keys radially arranged. with respect to the center ofthe disk and adapted to regulate its motion under the action of thespring motor, a higher order wheel, and means for effecting carryingoperation from said numeral disk to the higher order wheel, said meanscomprising a pawl having a pair of curved slots, a slide provided withpins extending through said curved slots, said disk being provided withmeans for reciprocating said slide, said disk also being provided withmeans for oscillating said pawl on one or the other of said pins inaccordance with the direction of rotation of said disk, and a restoringspring extended between said slide and pawl.

8. A device of the class described, comprising a numbered rotatabledisk, a spring for rotating said disk, a ratchet wheel rigid with saiddisk, a pawl for engaging said ratchet wheel and normally preventingrotation of the disk under the action of said spring, a pivoted bailarranged to rock said pawl out of engagement with said ratchet wheel,and manipulative means adapted to rock said bail to shift said pawl outof engagement with said ratchet wheel and to limit the rotation of thenumbered disk under the action of said spring.

Signed at Chicago this 2nd day of June,

CHARLES M. FITCH.

